What’s the difference between a run-on sentence and a long sentence? A run-on is usually long, but a long sentence is not necessarily a run-on. A run-on sentence is grammatically incorrect. It is comprised of two or more independent clauses that are not separated by a conjunction or punctuation.

Here are some examples:I am a teacher I am also a writer I love to swim.

I wanted to visit the Eifel Tower while I was in Paris, but I decided not to when I saw how tall it is since I suffer from acrophobia.

Without a comma or conjunctions, the two sentences are no more than thoughts strung together. Here they are written correctly:I am a teacher and a writer, and I love to swim.

I wanted to visit the Eifel Tower while in Paris, but I decided not to when I saw how tall it was. I suffer from acrophobia.

Here’s how a great passage would become a run-on sentence if the punctuation and the conjunction “or” were removed. Sherlock Holmes spoke it in Arthur Conan Doyle’s story, “The Adventures of the Creeping Man.”"My line of thoughts about dogs is analogous a dog reflects the family life whoever saw a frisky dog in a gloomy family a sad dog in a happy one snarling people have snarling dogs dangerous people have dangerous ones and their passing moods may reflect the passing moods of others."

Thankfully it was written:"My line of thoughts about dogs is analogous. A dog reflects the family life. Whoever saw a frisky dog in a gloomy family, or a sad dog in a happy one? Snarling people have snarling dogs, dangerous people have dangerous ones. And their passing moods may reflect the passing moods of others."

Long sentences should be written with a stylistic purpose, and if done so, can be literary works of art. Here are some of my favorites:“Its vanished trees, the trees that had made way for Gatsby’s house, had once pandered in whispers to the last and greatest of all human dreams; for a transitory enchanted moment man must have held his breath in the presence of this continent, compelled into an aesthetic contemplation he neither understood nor desired, face to face for the last time in history with something commensurate to his capacity for wonder.”—The Great Gatsby by F. Scott Fitzgerald

“It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness, it was the spring of hope, it was the winter of despair, we had everything before us, we had nothing before us, we were all going direct to Heaven, we were all going direct the other way—in short, the period was so far like the present period, that some of its noisiest authorities insisted on its being received, for good or for evil, in the superlative degree of comparison only.”--A Tale of Two Cities by Charles Dickens

You might have recently seen this well-crafted long sentence, since it’s been making the Facebook circuit. It’s English journalist and author, Bernard Levin’s, classic piece, On Quoting Shakespeare.“If you cannot understand my argument, and declare ``It's Greek to me'', you are quoting Shakespeare; if you claim to be more sinned against than sinning, you are quoting Shakespeare; if you recall your salad days, you are quoting Shakespeare; if you act more in sorrow than in anger; if your wish is farther to the thought; if your lost property has vanished into thin air, you are quoting Shakespeare; if you have ever refused to budge an inch or suffered from green-eyed jealousy, if you have played fast and loose, if you have been tongue-tied, a tower of strength, hoodwinked or in a pickle, if you have knitted your brows, made a virtue of necessity, insisted on fair play, slept not one wink, stood on ceremony, danced attendance (on your lord and master), laughed yourself into stitches, had short shrift, cold comfort or too much of a good thing, if you have seen better days or lived in a fool's paradise—why, be that as it may, the more fool you , for it is a foregone conclusion that you are (as good luck would have it) quoting Shakespeare; if you think it is early days and clear out bag and baggage, if you think it is high time and that that is the long and short of it, if you believe that the game is up and that truth will out even if it involves your own flesh and blood, if you lie low till the crack of doom because you suspect foul play, if you have your teeth set on edge (at one fell swoop) without rhyme or reason, then—to give the devil his due—if the truth were known (for surely you have a tongue in your head) you are quoting Shakespeare; even if you bid me good riddance and send me packing, if you wish I was dead as a door-nail, if you think I am an eyesore, a laughing stock, the devil incarnate, a stony-hearted villain, bloody-minded or a blinking idiot, then—by Jove! O Lord! Tut tut! For goodness' sake! What the dickens! But me no buts!—it is all one to me, for you are quoting Shakespeare.”